Fort Jackson was one of the four fur trading forts that lined the South Platte River area north of present-day metro Denver area. It was built by in the early part of 1837 at a cost of $12,000.00 by Peter A. Sarpy and Henry Fraeb and partially financed by the Western Division of the American Fur Company. It was the second or third fort built and was located about one and a half miles south of Fort Vasquez. The location of the fort has not been found as it is on private property and no physical remains survived or have been identified.